Cut slice from top of of each potato, scoop pulp to bowl, reserving shells. Mash pulp until free of lumps. Stir in veggies, parsley, milk, and pepper to taste. Add more milk to tast if necessary. Spoon mixture into shells, smoothing top. (potatoes can be prepared to this point, cooled and packaged for freezing). Sprinkle with cheese. Bake in 400F (200C) oven for 10 minutes or until filling is hot and cheese is melted.